Relay technology as a cost-effective network coverage expansion mode is introduced into a mobile communication system. Meanwhile, its introduction also aims to improve the quality of mobile communication services in the high-speed mobile scene. After the introduction, the wireless communication network architecture is shown in FIG. 1. A RN (Relay Node) is connected wirelessly to a cell (named Donor Cell of the RN) dominated by the DeNB (Donor evolved Node B) and then to a core network through a wired network. A mobile RN has two wireless interfaces totally, namely an Un interface between the mobile RN and the DeNB and an Uu interface between the user terminal belonging to the mobile RN (R-UE) and the mobile RN. It provides such processing functions as reception, decoding, protocol conversion and data forwarding between the Un and Uu interfaces.
A mobile RN has the following characteristics:
(1) It is a network-side node and arranged, managed and maintained by the operator.
(2) It can be installed on vehicles to provide services for a user terminal in the vehicles.
It is static relative to the equipment which it services.
(3) From the perspective of the user terminal, a mobile RN is an ordinary base station.
It manages independent cells, has independent physical layer cell identifications and sends independent synchronous signals, reference marks, etc. User terminals belonging to the mobile RN directly receive scheduling and control signals from the RN and directly send uplink control and feedback information to it.
(4) From the perspective of the DeNB, a mobile RN is similar to a user terminal. It interchanges the data with a core network through the DeNB. Meanwhile; it needs to measure the quality of signals at the Un interface and hands over according to different measurement results among different DeNB/Donor Cells (namely DeNB or/and Donor Cell, similarly hereinafter).
Not all eNBs are suitable as the DeNB of a mobile RN. DeNB and Donor Cell shall be configured to the mobile RN in advance. As a network-side node, for a RN similar to a fixed position RN (hereinafter referred to as a fixed RN), Donor Cells of a mobile RN are configured by the operator through an OAM (Operation and Maintenance) system of the RN.
The boot process of a fixed RN can be divided into two stages:
Stage I: after RN startup, select a cell (unnecessarily the one supporting a RN), attach it to a network using the same attachment process as UE (User terminal), and then acquire initial configuration parameters, such as DeNB/Donor Cell list and other parameters from OAM. Not all eNBs (evolved Node B)/Cells are suitable as DeNB/Donor Cell of a RN. To let a RN know the DeNB/Donor Cell it accesses, it is necessary to configure DeNB/Donor Cell for the RN. After the configuration, the RN is deattached from the network with the same deattachment process as UE and triggers the operation at stage II.
Stage II: a RN node selects a proper DeNB/Donor Cell for access from the DeNB/Donor Cell list acquired at stage I. After a series of preparations (such as creating interfaces S1 and X2, connecting the OAM, creating user panel carriers, etc.), a RN begins to provide services for UE. When it begins the normal operation, unless shutdown or abnormalities (for example, RN restart or serious problems of the wireless link of an interface between RN and DeNB), it will always be connected, and its position and DeNB/Donor Cell will be unchanged.
In the procedure of realizing the objects of the present invention, at least the following problems existing in the current technologies were found:
The prior art takes that a RN is fixed as a precondition. Thus, the DeNB/Donor Cell of a RN is always the same. After introducing a mobile RN, it is necessary to hand over DeNB/Donor Cell frequently when the mobile RN is moving. However, based on the prior art, it fails to configure a new DeNB/Donor Cell which can be accessed for the mobile RN.